Nouns

(n)spine, thorn, prickle, pricker, stickera small sharp-pointed tip resembling a spike on a stem or leaf
(n)gummed label, sticker, pasteran adhesive label
(n)poser, stumper, toughie, stickera particularly difficult or baffling question or problem
(n)dagger, stickera short knife with a pointed blade used for piercing or stabbing